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.TH VOACAPL 1 "SEO 2013" Linux "User Manuals"
.SH NAME
voacapl \- HF propagation prediction program
.SH SYNOPSIS
.B voacapl [\-s --silent --run-dir=directory_path --absorption-mode=mode]
.B voacap_directory
.I [inputfile]
\n
.B voacapl [\-s --silent --run-dir=directory_path --absorption-mode=mode]
.B voacap_directory
.I [inputfile outputfile]
\n
.B voacapl [\-s --silent --run-dir=directory_path --absorption-mode=mode]
.I voacap_directory
.B area calc
.I [areafile]
\n
.B voacapl [\-s]
.I voacap_directory
.B batch
\n
.B voacapl \-v
.SH DESCRIPTION
An implementation of VOACAP, the NTIA/ITS professional HF propagation prediction
program, originally developed for the Voice of America (VOA).   VOACAP reads an
input file and writes point-to-point path or area prediction data to an output
file(s). 'voacapl' is a version of the original source that has been modified
to enable compilation using GCC/GFortran.
\n
Only changes required to enable compilation using GCC have been made, the
underlying prediction algorithms remain unchanged.
\n
Voacapl input/output files follow exactly the same format as VOACAP and are not described here.  Details of these file formats may be found at www.voacap.com.
.SH OPTIONS
.IP -s
.IP --silent
Silent processing.  Reduces the number of messages printed to the screen while running.
.IP -v
Version.  Prints the version number and exits.
.IP --run-dir
Used to specify a location for the input and output files.  All other volatile
files (gainxx.dat etc.) will be saved in this directory.  This option is of most
use in server environments where multiple users may be running the application
concurrently and to facilitate clean-up after performing a prediction.
.IP --absorption-mode
Used to specify the absorption mode that should be used for the prediction, overriding
the value defined in version.w32.  Valid values are 'W' (normal), 'I' (IONCAP),
'A' (Alex's modifications with normal absorption) and 'a' (Alex's changes with
IONCAP absorption).
.IP voacap_directory
Specifies the path to the itshfbc directory, e.g. '~/itshfbc/' or '/usr/share/itshfbc'.  Read/write access is required to the sub-directories below itshfbc.
This parameter is required for program operation.(Note: See 'Bugs' section below for guidance on specifying the location of the itshfbc directory.)
.IP inputfile
Filename of the input file to process which should be located in the itshfbc/run directory.  If only the inputfile is specified, the default output filename (voacapx.out) will be used for program output.
.IP outputfile
Filename of the output file produced by the program.  Due to a limitation in the way in which command arguments are parsed, an input file must first be specified if an output file is to be specified, it is not possible to specify an output file only.  Input and output files are located below the "itshfbc/run" directory.
.IP area
Used to perform a VOAAREA calculation.  The original version of VOACAP permits the additional arguments CALC, SCREEN or PRINT to define the
operation of the VOAAREA operation.  voacapl currently only supports the 'calc' option.
.IP areafile
File containing the input data for an area calculation.  The path to the areafile must be given relative to the 'itshfbc/areadata/' directory.
.SH EXAMPLES
voacapl ~/itshfbc
\n
Reads the default input file (~/itshfbc/run/voacapx.dat) performs a prediction calculation and saves the results in the default output
file (~/itshfbc/run/voacapx.out).  In this example, the itshfbc directory is defined as a sub-directory of the users home folder.

voacapl ~/itshfbc infile.dat outfile.out
\n
Reads infile.dat and save the results of the calculations in the file outfile.out.  Both of the files should be located in the directory '~/itshfbc/run'.

voacapl --run-dir=/tmp/myrunndir ~/itshfbc infile.dat outfile.out
\n
Performs a prediction defined by infile.dat and saves the results of the calculations
in the file outfile.out.  The input file should be placed in the directory defined by the
run-dir parameter.
\n
voacapl --absorption-mode=a ~/itshfbc infile.dat outfile.out
\n
Sets the absorption model used by the prediction to 'a' (Alex's changes with
IONCAP absorption).  Reads infile.dat and save the results of the calculations
in the file outfile.out.  Both of the files should be located in the
directory '~/itshfbc/run'.

voacapl ~/itshfbc area calc testfile.voa

Performs an area calculation using the file 'testfile.voa' as input.  The output file(s) will be saved as testfile.vg_ in the same directory as testfile.voa.

voacapl ~/itshfbc batch

Performs a batch calculation using the file voacapw.asc as a template file to which the modifications defined in the circuit file (voacap.cir) are applied.
.SH FILES
.I itshfbc/
.RS
Voacapl requires access to a number of data files found within the 'itshfbc' directory structure.  Input and output files are written to itshfbc/run.

.SH ENVIRONMENT
VOACAP does not make use of any environmental variables.
.SH BUGS
Performance is unpredictable if the path to the itshfbc directory contains spaces or is more than 52 characters long.  This is a limitation of the legacy DOS based file handling procedures and will be addressed in future versions of voacapl.
.SH AUTHOR
This program was ported to GFortran by James Watson <jimwatson at mac dot com> using code that was originally developed by the NTIA/ITS
and is currently maintained by Greg Hand.
.SH "ACKNOWLEDGMENTS"
VOACAP is an improved and corrected version of IONCAP, retaining all of the theory as put forth by John Lloyd, George Haydon, Donald Lucas
and Larry Teters in the 1975-1985 time-frame with modifications which were suggested/approved by George Lane, Donald Lucas, George Haydon
and A. D. Spaulding.  Major improvements in efficiency, coding corrections and ease of understanding the IONCAP program were made by
Franklin Rhoads of the U.S. Navy Research Laboratory under the sponsorship of the Voice of America (1985-1996). Many of the newer
features in VOACAP and VOAAREA were designed and implemented by Gregory Hand at the Institute for Telecommunication Sciences who
created VOAAREA and made many significant improvements to VOACAP.

Porting this program to GFortran would not be possible without the generous help and assistance of Gregory Hand.

Portions of this man page have been reproduced with permission from the www.voacap.com website, maintained by Jari Perkiomaki.

.SH "SEE ALSO"
www.voacap.com
